How to Deal with Common Weather Hazards on the Lake

Published Jun 18 2014 07:20 PM EDT

NOAA

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Check the Forecast Before Hitting the LakeChecking the forecast and staying alert for changing weather conditions is extremely important if you are planning a day at the lake. The biggest weather-related dangers for local boaters and swimmers are strong winds, lightning, and heat-related illnesses. Strong winds cause the most problems as they often create large waves, which can carry away swimmers and capsize or swamp small boats. It is important to check the forecast before you begin your trip and remain alert for changing weather conditions while on the water.

Otherwise...by the time you realize you are in danger you may not have enough time to get to safety. While on the water, listen to NOAA weather radio for forecast updates and possible weather advisories, watches, and warnings. Always let someone know where you are going and when you plan to be back.

Strong WindsStrong winds are the biggest weather-related threat to boaters on area lakes. Strong winds create large waves and make waters choppy. Wind Boaters and swimmers must be aware that wind and wave conditions on area lakes can change rapidly and often vary greatly from place to place.

Large wind-driven waves can wash over the side of a small craft and fill it with water. In addition, if a large wave hits a vessel at just the right angle, it could capsize a small boat, canoe, or kayak. Swimmers are also vulnerable to the effects of winds and large waves. Inexperienced swimmers can tire very quickly while trying to swim in large waves. Improper floatation devices, such as pool toys, are sometimes used to stay afloat. These toys can blow or drift away, stranding swimmers far from shore.

ThunderstormsA general rule of thumb...the longer the distance the wind travels over the water, the larger the waves will be. When strong winds are expected, it is best to avoid large stretches of open water such as the center of the lake, where waves will be larger. Wind-generated wave heights are not only affected by the orientation of the lake relative to the wind direction, but also differ in height based on what side of the lake you are on.. For example, if you have a large lake and winds are blowing from the west, waves on the east side of the lake (the leeward side) will be larger than waves on the west side of the lake (the windward side). Waves will be smaller in coves or inlets that are shielded from the winds. If your boat becomes disabled during strong winds, throw an anchor or empty bucket attached by a line into the water to slow drifting action.

Thunderstorm winds in particular pose a threat to boaters. Winds near a thunderstorm can increase very suddenly and without warning, leaving boaters little chance to seek shelter in time. Thunderstorms over area lakes can occur year-round and at any time of the day. However...they occur most often during the afternoon and evening hours from July to mid-September in association with the summer monsoon. One of the biggest dangers thunderstorms pose for boaters is strong winds from thunderstorm outflow boundaries. An outflow boundary occurs at the surface as rain-cooled air descends and spreads out of a collapsing thunderstorm. Winds associated with these boundaries increase very suddenly and frequently reach sustained wind speeds of greater than 30 mph.

These boundaries can travel for 100 miles or more and are sometimes visible as walls of dust. If a thunderstorm or thunderstorm outflow boundary is approaching your location the best course of action is to get to shore, get out of your boat, and find shelter away from the water as quickly as possible. If you are unable to get to shore in time, prepare for choppy waters and make sure everyone in your boat is wearing a life jacket. Secure people and heavy objects in the center of the boat. Go to a sheltered cove or inlet and wait the storm out. Better yet, on days when thunderstorms are possible, remain alert and head to shore immediately when you see thunderstorms beginning to develop. Boat ramps can get very crowded when everyone tries to get off the lake at once!

Always check the forecast before heading out to the lake. Pay special attention to forecast wind speeds and thunderstorm potential. If a Lake Wind Advisory has been issued or there is a high probability of thunderstorms occurring; you may want to consider postponing your trip.

Extreme HeatTo protect yourself from heat related illnesses while on the lake:

Limit outdoor activity during the hottest part of the day, typically between 11 AM and 7 PM.

Wear lightweight, light-colored clothing.

Drink plenty of water or other non-alcoholic fluids even if you do not feel thirsty. Caffeine and alcohol should be avoided since they can worsen the effects of heat on your body.

Eat smaller, more frequent meals.

If you or someone else begins to shows symptoms of a heat-related illness, stop activities and find a cool place. Seek medical attention if necessary.